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Ma M, Yang W, Cai Z, Wang P, Li H, Mi R, Jiang Y, Xie Z, Sui P, Wu Y, Shen H. SMAD-specific E3 ubiquitin ligase 2 promotes angiogenesis by facilitating PTX3 degradation in MSCs from patients with ankylosing spondylitis. STEM CELLS (DAYTON, OHIO) 2021; 39:581-599. [PMID: 33547700 PMCID: PMC8248389 DOI: 10.1002/stem.3332] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 11/18/2020] [Accepted: 12/10/2020] [Indexed: 12/13/2022]
Abstract
Dysregulated angiogenesis of mesenchymal stem cells (MSCs) is closely related to inflammation and disrupted bone metabolism in patients with various autoimmune diseases. However, the role of MSCs in the development of abnormal angiogenesis in patients with ankylosing spondylitis (AS) remains unclear. In this study, we cultured human umbilical vein endothelial cells (HUVECs) with bone marrow-derived MSCs from patients with AS (ASMSCs) or healthy donors (HDMSCs) in vitro. Then, the cocultured HUVECs were assayed using a cell counting kit-8 (CCK-8) to evaluate the cell proliferation. A wound healing assay was performed to investigate cell migration, and a tube formation assay was conducted to determine the angiogenesis efficiency. ASMSCs exhibited increased angiogenesis, and increased expression of SMAD-specific E3 ubiquitin ligase 2 (Smurf2) in MSCs was the main cause of abnormal angiogenesis in patients with AS. Downregulation of Smurf2 in ASMSCs blocked angiogenesis, whereas overexpression of Smurf2 in HDMSCs promoted angiogenesis. The pro-angiogenic effect of Smurf2 was confirmed by the results of a Matrigel plug assay in vivo. By functioning as an E3 ubiquitin ligase in MSCs, Smurf2 regulated the levels of pentraxin 3 (PTX3), which has been shown to suppress angiogenesis through the PTX3-fibroblast growth factor 2 pathway. Moreover, Smurf2 transcription was regulated by activating transcription factor 4-induced endoplasmic reticulum stress. In conclusion, these results identify novel roles of Smurf2 in negatively regulating PTX3 stability and promoting angiogenesis in ASMSCs.
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Affiliation(s)
- Mengjun Ma
- Department of Orthopedics, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, People's Republic of China
| | - Wen Yang
- Department of Orthopedics, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, People's Republic of China
| | - Zhaopeng Cai
- Department of Orthopedics, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, People's Republic of China
| | - Peng Wang
- Department of Orthopedics, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, People's Republic of China
| | - Hongyu Li
- Department of Orthopedics, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, People's Republic of China
| | - Rujia Mi
- Center for Biotherapy, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, People's Republic of China
| | - Yuhang Jiang
- Department of Orthopedics, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, People's Republic of China
| | - Zhongyu Xie
- Department of Orthopedics, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, People's Republic of China
| | - Pengfei Sui
- State Key Laboratory of Cell Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, People's Republic of China
| | - Yanfeng Wu
- Center for Biotherapy, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, People's Republic of China
| | - Huiyong Shen
- Department of Orthopedics, The Eighth Affiliated Hospital of Sun Yat-sen University, Shenzhen, Guangdong, People's Republic of China.,Department of Orthopedics, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, Guangdong, People's Republic of China
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Lear TB, Lockwood KC, Larsen M, Tuncer F, Kennerdell JR, Morse C, Valenzi E, Tabib T, Jurczak MJ, Kass DJ, Evankovich JW, Finkel T, Lafyatis R, Liu Y, Chen BB. Kelch-like protein 42 is a profibrotic ubiquitin E3 ligase involved in systemic sclerosis. J Biol Chem 2020; 295:4171-4180. [PMID: 32071084 PMCID: PMC7105301 DOI: 10.1074/jbc.ac119.012066] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 02/07/2020] [Indexed: 01/08/2023] Open
Abstract
Systemic scleroderma (SSc) is an autoimmune disease that affects over 2.5 million people globally. SSc results in dysfunctional connective tissues with excessive profibrotic signaling, affecting skin, cardiovascular, and particularly lung tissue. Over three-quarters of individuals with SSc develop pulmonary fibrosis within 5 years, the main cause of SSc mortality. No approved medicines to manage lung SSc currently exist. Recent research suggests that profibrotic signaling by transforming growth factor β (TGF-β) is directly tied to SSc. Previous studies have also shown that ubiquitin E3 ligases potently control TGF-β signaling through targeted degradation of key regulatory proteins; however, the roles of these ligases in SSc-TGF-β signaling remain unclear. Here we utilized primary SSc patient lung cells for high-throughput screening of TGF-β signaling via high-content imaging of nuclear translocation of the profibrotic transcription factor SMAD family member 2/3 (SMAD2/3). We screened an RNAi library targeting ubiquitin E3 ligases and observed that knockdown of the E3 ligase Kelch-like protein 42 (KLHL42) impairs TGF-β-dependent profibrotic signaling. KLHL42 knockdown reduced fibrotic tissue production and decreased TGF-β-mediated SMAD activation. Using unbiased ubiquitin proteomics, we identified phosphatase 2 regulatory subunit B'ϵ (PPP2R5ϵ) as a KLHL42 substrate. Mechanistic experiments validated ubiquitin-mediated control of PPP2R5ϵ stability through KLHL42. PPP2R5ϵ knockdown exacerbated TGF-β-mediated profibrotic signaling, indicating a role of PPP2R5ϵ in SSc. Our findings indicate that the KLHL42-PPP2R5ϵ axis controls profibrotic signaling in SSc lung fibroblasts. We propose that future studies could investigate whether chemical inhibition of KLHL42 may ameliorate profibrotic signaling in SSc.
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Affiliation(s)
- Travis B Lear
- Department of Environmental and Occupational Health, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania 15261; Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Karina C Lockwood
- Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Mads Larsen
- Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Ferhan Tuncer
- Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Jason R Kennerdell
- Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Christina Morse
- Division of Rheumatology and Clinical Immunology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Eleanor Valenzi
- Division of Rheumatology and Clinical Immunology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Tracy Tabib
- Division of Rheumatology and Clinical Immunology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Michael J Jurczak
- Division of Endocrinology and Metabolism, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Daniel J Kass
- Dorothy P. and Richard P. Simmons Center for Interstitial Lung Disease, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - John W Evankovich
- Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213; Acute Lung Injury Center of Excellence, Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Toren Finkel
- Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213; Division of Cardiology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Robert Lafyatis
- Division of Rheumatology and Clinical Immunology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213
| | - Yuan Liu
- Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213; Acute Lung Injury Center of Excellence, Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213.
| | - Bill B Chen
- Aging Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213; Acute Lung Injury Center of Excellence, Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213; Vascular Medicine Institute, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania 15213.
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Long Y, Chen W, Du Q, Zuo X, Zhu H. Ubiquitination in Scleroderma Fibrosis and Its Treatment. Front Immunol 2018; 9:2383. [PMID: 30386338 PMCID: PMC6199354 DOI: 10.3389/fimmu.2018.02383] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 09/25/2018] [Indexed: 12/11/2022] Open
Abstract
Scleroderma (systemic sclerosis, SSc) is a highly heterogeneous rheumatic disease, and uncontrolled fibrosis in visceral organs is the major cause of death in patients. The transforming growth factor-β (TGF-β) and WNT/β-catenin signaling pathways, along with signal transducer and activator of transcription 3 (STAT3), play crucial roles in this fibrotic process. Currently, no therapy is available that effectively arrests or reverses the progression of fibrosis in patients with SSc. Ubiquitination is an important post-translational modification that controls many critical cellular functions. Dysregulated ubiquitination events have been observed in patients with systemic lupus erythematosus, rheumatoid arthritis and fibrotic diseases. Inhibitors targeting the ubiquitination pathway have considerable potential for the treatment of rheumatic diseases. However, very few studies have examined the role and mechanism of ubiquitination in patients with SSc. In this review, we will summarize the molecular mechanisms of ubiquitination in patients with SSc and explore the potential targets for treatment.
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Affiliation(s)
- Ying Long
- Department of Rheumatology, Xiangya Hospital, Central South University, Changsha, China
| | - Weilin Chen
- Department of Rheumatology, Xiangya Hospital, Central South University, Changsha, China
| | - Qian Du
- Department of Rheumatology, Xiangya Hospital, Central South University, Changsha, China
| | - Xiaoxia Zuo
- Department of Rheumatology, Xiangya Hospital, Central South University, Changsha, China
| | - Honglin Zhu
- Department of Rheumatology, Xiangya Hospital, Central South University, Changsha, China
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Meiners S, Evankovich J, Mallampalli RK. The ubiquitin proteasome system as a potential therapeutic target for systemic sclerosis. Transl Res 2018; 198:17-28. [PMID: 29702079 DOI: 10.1016/j.trsl.2018.03.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/20/2018] [Accepted: 03/24/2018] [Indexed: 01/16/2023]
Abstract
The present review aims to summarize available knowledge on the role of the ubiquitin-proteasome system (UPS) in the pathogenesis of scleroderma and scleroderma-related disease mechanisms. This will provide the reader with a more mechanistic understanding of disease pathogenesis and help to identify putative novel targets within the UPS for potential therapeutic intervention. Because of the heterogenous manifestations of scleroderma, we will primarily focus on conserved mechanisms that are involved in the development of lung scleroderma phenotypes.
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Affiliation(s)
- Silke Meiners
- Comprehensive Pneumology Center (CPC), University Hospital, Ludwig Maximilians University, Helmholtz Zentrum München, Germany; Comprehensive Pneumology Center, Munich (CPC-M), Germany; Member of the German Center for Lung Research (DZL), Munich, Germany.
| | - John Evankovich
- Pulmonary, Allergy, and Critical Care Medicine, Acute Lung Injury Center of Excellence, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Rama K Mallampalli
- Pulmonary, Allergy, and Critical Care Medicine, Acute Lung Injury Center of Excellence, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA; Department of Cell Biology and Physiology, University of Pittsburgh, Pittsburgh, PA, USA; Medical Specialty Service Line, Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, PA, USA.
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Huang XL, Zhang L, Duan Y, Wang YJ, Zhao JH, Wang J. E3 ubiquitin ligase: A potential regulator in fibrosis and systemic sclerosis. Cell Immunol 2016; 306-307:1-8. [PMID: 27406900 DOI: 10.1016/j.cellimm.2016.07.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 05/17/2016] [Accepted: 07/05/2016] [Indexed: 01/11/2023]
Abstract
Systemic sclerosis (SSc) is an autoimmune disease characterized by fibrosis in the skin and internal organs. The pathogenesis of SSc is not completely understood until now. Recently, many studies have focused on the role of E3 ubiquitin ligases in organ fibrosis. However, the possible regulatory mechanisms of E3 ubiquitin ligases in fibrosis and SSc are not well documented. In this review, we summarized that E3 ubiquitin ligases regulated fibrosis through ubiquitin-mediated degradation of TGF-β/Smad signaling pathway. Moreover, E3 ubiquitin ligases participated in regulating fibrosis by other methods, such as inducing epithelial transition to mesenchymal cell, enhancing the production of TGF-β and protecting activated hepatic stellate cells from apoptosis. However, the specific regulatory mechanisms of E3 ubiquitin ligases in scleroderma is still not fully understood. There are more works to be done to specify the mechanism of E3 ubiquitin ligases in regulation of fibrosis in SSc.
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Affiliation(s)
- Xiao-Lei Huang
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, China
| | - Li Zhang
- Medical Genetics Center, Anhui Medical College, Hefei, China
| | - Yu Duan
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, China
| | - Yu-Jie Wang
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, China
| | - Jiu-Hua Zhao
- West Anhui Health Vocational College, Lu'an, Anhui, China
| | - Jing Wang
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, China.
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Zhang Z, Finnerty CC, He J, Herndon DN. Smad ubiquitination regulatory factor 2 expression is enhanced in hypertrophic scar fibroblasts from burned children. Burns 2011; 38:236-46. [PMID: 21920670 DOI: 10.1016/j.burns.2011.08.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 08/09/2011] [Accepted: 08/12/2011] [Indexed: 12/12/2022]
Abstract
Transforming growth factor-β1 (TGF-β1) plays a key role in hypertrophic scar formation. A lot of studies have shown that TGF-β1 stimulates fibroblast proliferation, collagen production, and α-smooth muscle actin (α-SMA) expression, inhibits matrix degradation and eventually leads to scar formation. Smad proteins are important intracellular mediators of TGF-β1 signaling, and Smad ubiquitination regulatory factor 2 (Smurf2), an ubiquitin ligase for Smads, plays critical roles in the regulation of TGF-β1/Smad signaling. It was reported that Smurf2 was abnormally expressed during the process of liver fibrosis and lung fibrosis. Hypertrophic scarring is a fibroproliferative disorder of the dermis that occurs following wounding. However, little is known about the expression of Smurf2 in hypertrophic scarring. We hypothesized that TGF-β1 signaling cannot be disrupted after wound epithelialization probably due to abnormal expression of Smurf2 in hypertrophic scar fibroblasts. In the present study, we found that hypertrophic scar fibroblasts exhibited increased Smurf2 protein and mRNA levels compared with normal fibroblasts, and the expression of Smurf2 gradually increased in hypertrophic scar fibroblasts after TGF-β1 stimulation. Furthermore, we transfected Smurf2 siRNA into hypertrophic scar fibroblasts, and we found that silencing the expression of Smurf2 in hypertrophic scar fibroblasts dramatically reduced TGF-β1 production, inhibited TGF-β1-induced α-SMA expression and inhibited TGF-β1-induced collagen I synthesis. Our results suggest that the enhanced expression of Smurf2 is involved in the progression of hypertrophic scarring.
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Affiliation(s)
- Zhi Zhang
- Department of Burn and Plastic Surgery, Guangzhou Red Cross Hospital, Jinan University, Guangzhou 510220, China.
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Cai Y, Shen XZ, Zhou CH, Wang JY. Abnormal expression of Smurf2 during the process of rat liver fibrosis. ACTA ACUST UNITED AC 2006; 7:237-45. [PMID: 17054587 DOI: 10.1111/j.1443-9573.2006.00275.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Liver fibrosis is a prelude of liver cirrhosis. Currently the molecular mechanism of liver fibrosis is not clear. The purpose of this study is to screen the abnormally expressed genes of liver fibrosis and to illustrate the changes of Smurf2 expression in the process of liver fibrosis. METHODS A liver fibrosis model was established in rats by injection of tetrachlormethane (CCl(4)). A cDNA microarray analysis was performed on the liver at mid-stage of fibrosis. Thereafter, a semi-quantitative RT-PCR, Western blot analysis and immunohistochemistry test were performed for determining Smurf2, Smad2 and SnoN at week 1, 2, 4 and 8 of establishing the liver fibrosis model. RESULTS Smurf2, FGG, PTAFR, CYP2D6, among others, increased in the fibrosis liver and a semi-quantitative RT-PCR confirmed the reliability of the cDNA microarray analysis. Smurf2 in the liver fibrosis model group was at the same level as that of control group at week 1, but decreased at week 2 and 8 and increased at the week 4. Smad2 increased at week 2 and 8 but increased at week 4. However, Smad2 mRNA increased to the same level at week 4 as that at week 2 and 8. The decrease of Smad2 at week 4 may be due to the enhancement of ubiquitination and proteolytic degradation of Smad2 by the increase of Smurf2. SnoN decreased at week 4 and 8 because of the ubiquitination and degradation caused by Smurf2. The decrease of SnoN may explain the progress of liver fibrosis in spite of the decrease of Smad2 at week 4. CONCLUSION This study screened the abnormally expressed genes of liver fibrosis and illustrated the changes of Smurf2, Smad2 and SnoN during the process of liver fibrosis.
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Affiliation(s)
- Yu Cai
- Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai 200032, China
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Pannu J, Gore-Hyer E, Yamanaka M, Smith EA, Rubinchik S, Dong JY, Jablonska S, Blaszczyk M, Trojanowska M. An increased transforming growth factor beta receptor type I:type II ratio contributes to elevated collagen protein synthesis that is resistant to inhibition via a kinase-deficient transforming growth factor beta receptor type II in scleroderma. ACTA ACUST UNITED AC 2004; 50:1566-77. [PMID: 15146427 DOI: 10.1002/art.20225] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
OBJECTIVE Aberrant transforming growth factor beta (TGFbeta) signaling has been implicated in the pathogenesis of scleroderma (systemic sclerosis [SSc]), but the contribution of specific components in this pathway to SSc fibroblast phenotype remains unclear. This study was undertaken to delineate the role of TGFbeta receptor type I (TGFbetaRI) and TGFbetaRII in collagen overexpression by SSc fibroblasts. METHODS Primary dermal fibroblasts from SSc patients and healthy adults were studied (n = 10 matched pairs). Adenoviral vectors were generated for TGFbetaRI (AdTGFbetaRI), TGFbetaRII (AdTGFbetaRII), and kinase-deficient TGFbetaRII (AdDeltakRII). TGFbetaRI basal protein levels were analyzed by (35)S-methionine labeling/immunoprecipitation and immunohistochemistry. Type I collagen and TGFbetaRII basal protein levels were analyzed by Western blot and newly secreted collagen by (3)H-proline incorporation assay. RESULTS Analysis of endogenous TGFbetaRI and TGFbetaRII protein levels revealed that SSc TGFbetaRI levels were increased 1.7-fold (P = 0.008; n = 7) compared with levels in healthy controls, while TGFbetaRII levels were decreased by 30% (P = 0.03; n = 7). This increased TGFbetaRI:TGFbetaRII ratio correlated with SSc collagen overexpression. To determine the consequences of altered TGFbetaRI:TGFbetaRII ratio on collagen expression, healthy fibroblasts were transduced with AdTGFbetaRI or AdTGFbetaRII. Forced expression of TGFbetaRI in the range corresponding to elevated SSc TGFbetaRI levels increased basal collagen expression in a dose-dependent manner, while similar TGFbetaRII overexpression had no effect, although transduction of fibroblasts at higher multiplicities of infection led to a marked reduction of basal collagen levels. Blockade of TGFbeta signaling via AdDeltakRII resulted in approximately 50% inhibition of basal collagen levels in healthy fibroblasts and in 5 of 9 SSc cell lines. A subset of SSc fibroblasts (4 of 9 cell lines) was resistant to this treatment. SSc fibroblasts with the highest levels of TGFbetaRI were the least responsive to collagen inhibition via DeltakRII. CONCLUSION This study indicates that an increased TGFbetaRI:TGFbetaRII ratio may underlie aberrant TGFbeta signaling in SSc and contribute to elevated basal collagen production, which is insensitive to TGFbeta signaling blockade via DeltakRII.
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Affiliation(s)
- Jaspreet Pannu
- Division of Rheumatology and Immunology, Medical University of South Carolina, 96 Jonathan Lucas Street, Charleston, SC 29425, USA
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